RELEVANCE: This study will create a database of the above elbow amputee population being treated within the VA hospital system and a patient classification system for use in the research and development of new prosthetic technologies. This work aims to collect anatomical, quality of life and biomechanical data that will be used to optimize the design of an above-elbow osseointegrated implant being developed to improve the quality of life for Veterans amputees. Dr. Sarina Sinclair and her collaborators have the clinical and research foundation on which to successfully complete this work. Direct skeletal attachment of prosthetic limbs through osseointegration (OI), is currently being tested and optimized at the George E. Wahlen VA Salt Lake City Health Care System. OI technology is being developed to improve prosthetic attachment, improve functional outcomes and reduce complications commonly associated with socket interface systems. Our research team is currently conducting an FDA approved Early Feasibility Study of an OI prosthesis in veteran transfemoral amputees. The knowledge gained from our successful transfemoral OI program is now being applied to upper extremity amputees. It is our goal to offer transhumeral (TH) amputees an OI system that will enable them to take full advantage of the advanced upper extremity prosthetic technologies that have been developed in recent years to maximize function. This study on TH amputees will be the first to gather comprehensive anatomical, quality of life and functional data that will be used to develop a classification system to identify candidates for future clinical trials. AIMS: Aim 1) Create a database of US Veterans with transhumeral amputations for use in the development of prosthetic technologies through a chart review, clinical referrals and personal interviews; Aim 2) Conduct a full clinical evaluation of upper extremity bone and soft tissue anatomy via physical exam, gross anatomical measurements, X-rays, DEXA and CT scans; Aim 3) Assess the functional capabilities of TH amputees being treated within the VA system utilizing validated tools for monitoring range of motion, biomechanics, activity, impairment and patient satisfaction; Aim 4) Develop a patient classification system of TH amputees that can be used to identify appropriate candidates for clinical trials of prosthetic technologies. METHODS: A national search will be conducted for veteran above elbow amputees. Medical records will be reviewed to gather demographic and epidemiologic data including: cause, time since amputation, residual limb length, prosthetic use and comorbidities. Patients that meet a predetermined set of inclusion criteria will be sent a letter informing them of the study and requesting a response if they have interest in OI technologies. If consented to attend a screening visit, participants will undergo the following assessments: Anterior/Posterior and Lateral X-rays, Computed Tomography (CT) scan, DEXA scan, Physical examination of residual limb, self report assessments of pain, quality of life and function, functional assessment performing activities of daily living with a focus on range of motion, and kinematic assessment in a Motion Capture Laboratory. It is our goal to complete onsite screening of 50 TH amputees within a three-year period. Data will be interpreted to develop a system to classify subjects based on bone quality, function, pain and prosthetic limitations. This system will be used to identify appropriate candidates for future clinical trials an OI device and other advance prosthetic technologies. SIGNIFICANCE: This work has the potential to significantly improve VA clinical care for amputees by providing a previously uncollected comprehensive data set from veteran transhumeral amputees to the research community and healthcare providers. A new classification system will be developed that can be applied towards selection of appropriate candidates for future prosthetics research and in clinical practice to improve the Veteran's function and overall quality of life.